Q&A with Mike Laidley, vice president of Orbital ATK’s Next Generation Launch program (members only)

The demands of launching the first in an upgraded line of U.S. Air Force GPS navigation satellites, including a late load of extra fuel for the spacecraft and a military policy of reserving fuel to eliminate space junk, will keep SpaceX from recovering the first stage of its Falcon 9 rocket following liftoff Thursday from Cape Canaveral, according to mission managers.

The Antares rocket, Orbital ATK’s medium-class booster now with modern RD-181 engines, launches at 7:45 p.m. EDT (2345 GMT) from NASA’s Wallops Flight Facility on the eastern shore of Virginia.

The Air Force’s robotic X-37B mini space shuttle swooped out of obscurity today after 718 days spent in orbit on a secretive military mission, touching down at the Kennedy Space Center’s orbiter runway on autopilot, the military announced on Twitter.